成都信息工程大学（成都信工学院）：《大学英语》PPT教学课件（第三册）Unit 4 Eatraterrestrials

Unit Extraterrestrials

Unit 4 Extraterrestrials

Unidentified Flying object Encarta Encyclopedia, Julian Baum Science Source/ Photo Researchers, Inc

Unidentified Flying Object

Unidentified Flying object(UFO), any object or light, reportedly sighted in the sky that cannot be immediately explained by the observer. Sightings of unusual aerial henomena date back to ancient times but UFOs(sometimes called flying saucers became widely discussed only after the first widely publicized U.S. sighting in 1947. Many thousands of such observations have since been reported worldwide

Unidentified Flying Object (UFO), any object or light, reportedly sighted in the sky, that cannot be immediately explained by the observer. Sightings of unusual aerial phenomena date back to ancient times, but UFOs (sometimes called flying saucers) became widely discussed only after the first widely publicized U.S. sighting in 1947. Many thousands of such observations have since been reported worldwide

e At least 90 percent of UFO sightings can be identified as conventional objects although time-consuming investigations are often necessary for such identification The objects most often mistaken for UFOS are bright planets and stars, aircraft, birds, balloons, kites, aerial flares peculiar clouds, meteors, and satellites. The remaining sightings most likely can be attributed to other mistaken sightings or to inaccurate reporting, hoaxes, or delusions although to disprove all claims made about UFOs is impossible

At least 90 percent of UFO sightings can be identified as conventional objects, although time-consuming investigations are often necessary for such identification. The objects most often mistaken for UFOs are bright planets and stars, aircraft, birds, balloons, kites, aerial flares, peculiar clouds, meteors, and satellites. The remaining sightings most likely can be attributed to other mistaken sightings or to inaccurate reporting, hoaxes, or delusions, although to disprove all claims made about UFOs is impossible

e From 1947 to 1969 the u.s. air force investigated UFOS as a possible threat to national security. a total of 12, 618 reports was received, of which 701 reports, or 5.6 percent, were listed as unexplained. The air force concluded that " no UFO reported, investigated and evaluated by the air force has ever given any indication of threat to our national security Since 1969 no agency of the U.S. government has had any active program of UFO investigation

From 1947 to 1969 the U.S. Air Force investigated UFOs as a possible threat to national security. A total of 12,618 reports was received, of which 701 reports, or 5.6 percent, were listed as unexplained. The air force concluded that “no UFO reported, investigated, and evaluated by the Air Force has ever given any indication of threat to our national security.” Since 1969 no agency of the U.S. government has had any active program of UFO investigation

o In 1997 the U.S. Central Intelligence Agency (CIA) admitted that the U.S. military had deceived the american public in an effort to hide information about high-altitude spy planes. These planes the Lockheed U-2A and the lockheed sr-71, accounted for over half of the UFo reports during the late 1950s and 1960s

In 1997 the U.S. Central Intelligence Agency (CIA) admitted that the U.S. military had deceived the American public in an effort to hide information about high-altitude spy planes. These planes, the Lockheed U-2A and the Lockheed SR-71, accounted for over half of the UFO reports during the late 1950s and 1960s

e Some persons nevertheless believe that UFOS are extraterrestrial spacecraft, even though no scientifically valid evidence supports that belief. The possibility of extraterrestrial civilizations is not the stumbling block; most scientists grant that intelligent life may well exist elsewhere in the universe. a fully convincing UFO photograph of a craftlike object has yet to be taken however and the scientific method requires that highly speculative explanations should not be adopted unless all of the more ordinary explanations can be ruled out

Some persons nevertheless believe that UFOs are extraterrestrial spacecraft, even though no scientifically valid evidence supports that belief. The possibility of extraterrestrial civilizations is not the stumbling block; most scientists grant that intelligent life may well exist elsewhere in the universe. A fully convincing UFO photograph of a craftlike object has yet to be taken, however, and the scientific method requires that highly speculative explanations should not be adopted unless all of the more ordinary explanations can be ruled out

e UFO enthusiasts persist, however, and some persons even claim to have been abducted and taken aboard UFOS.(a close encounter of the third kind is UFo terminology for an alleged encounter between humans and visitors from outer space )No one has produced scientifically acceptable proof of these claims

UFO enthusiasts persist, however, and some persons even claim to have been abducted and taken aboard UFOs. (A close encounter of the third kind is UFO terminology for an alleged encounter between humans and visitors from outer space.) No one has produced scientifically acceptable proof of these claims

Obiectives 1. understand the main idea( some E.T. has tried to establish relationship with people on Earth but found their friendly initiative rejected due to misunderstandings.) 2. appreciate the difference between formal speech and informal speech 3. grasp the key language points and grammatical structures in the text

Objectives • 1. understand the main idea ( some E.T. has tried to establish relationship with people on Earth, but found their friendly initiative rejected due to misunderstandings. ). • 2. appreciate the difference between formal speech and informal speech. • 3. grasp the key language points and grammatical structures in the text

Background Venus the second major planet in order of distance from the Sun. Also known as Hesperus the evening star, or Phosphorus, the morning star Venus can be the brightest object in the sky after the Sun and moon and follows a near- circular path some 106 million kilometres from the Sun taking 225 days to complete one orbit

Background • Venus the second major planet in order of distance from the Sun. Also known as Hesperus, the evening star, or Phosphorus, the morning star, Venus can be the brightest object in the sky after the Sun and Moon and follows a near￾circular path some 106 million kilometres from the Sun, taking 225 days to complete one orbit